WASHINGTON --- The chief of Naval Operations says he is devastated and heartbroken over the collision of the Arleigh Burke-class guided-missile destroyer USS John S. McCain, and has ordered a worldwide operational pause as fleet commanders assess practices.

"I just want to convey again that our thoughts and prayers are with the crew of the John S. McCain and their families as we work together through this very, very difficult time," Navy Adm. John M. Richardson told reporters today at the Pentagon.

Ten sailors were missing and five injured after the McCain collision, which occurred east of the Strait of Malacca and Singapore, early today local time, as reported 6:24 a.m. Japan Standard Time, according to the U.S. 7th Fleet.

The collision involved the McCain and the merchant vessel Alnic MC. The McCain arrived at Changi Naval Base in Singapore in the afternoon.

Seven sailors were killed June 17, when the Arleigh Burke-class destroyer USS Fitzgerald and a cargo ship collided off the coast of Japan.

"I am sure you all felt the same way that I did -- just devastated, and really just heartbroken at having to deal with this again," Richardson said today.

Serious Incident, Operational Pause Directed

Richardson directed the Navy to take an "operational pause" in all of its fleets around the world, to allow fleet commanders to assess and review with their commands the fundamental practice to safe and effective operations.

He said he envisions the pause lasting "one to two days," but said he is leaving the specifics to the fleet commanders.

"This is obviously an extremely serious incident and is the second such incident in a very short period of time, within inside of three months and very similar as well and is the last of a series of incidents in the Pacific fleet in particular," the admiral said.

In addition to the operational pause, Richardson said he directed a more comprehensive review to find the contributing factors and root causes of the incidents.

U.S. Fleet Forces Command Chief to Lead Comprehensive Review

Richardson said he tasked Navy Adm. Phil Davidson, the commander of U.S. Fleet Forces Command, to take charge of a comprehensive review that will include representation from throughout the Navy, as well as from other services and the private sector.

That review will look at the processes the Navy uses to train and certify the forward deployed forces in Japan. Another area for examination, as Richardson outlined, is how the Navy trains and certifies its surface warfare community, including tactical and navigational proficiency.

"My hope is that we will learn, continue to improve in the short term, validating that we are sound on the fundamentals and if not then we'll take action to correct that, and then look at broader, more systemic issues that we may find through this comprehensive review," Richardson said.

The comprehensive review is in addition to the investigations into the Fitzgerald and McCain, he added.